Question: $\dfrac{9}{12} + \dfrac{1}{4} = {?}$
$ = {\dfrac{9 \times 1}{12 \times 1}} + {\dfrac{1 \times 3}{4 \times 3}} $ $ = {\dfrac{9}{12}} + {\dfrac{3}{12}} $ $ = \dfrac{{9} + {3}}{12} $ $ = \dfrac{12}{12}$